Belt supporting and aligning structures



Feb. 19, 1957 A. J. KINDIG BELT SUPPORTING AND ALIGNING STRUCTURES Filed June 22, 1954 2 Sheets-Sheet l INVENTOR,

k ARNIE. J. KINDIG,

Feb. 19, 1957 A. J. KlNDlG BELT SUPPORTING AND ALIGNING STRUCTURES Filed June 22; 1954 2 Sheets-Sheet 2 Q INVENTOR,

AENIE J. KINDIG, BY

United States Patent Ofiice BELT SUPPORTING AND ALIGNING STRUCTURES Arnie J. Kindig, Columbus, Ohio, assignor to The Jeffrey Manufacturing Company, a corporation of Ohio Application June 22, 1954, Serial No. 438,534 4 Claims. c1. 74-241 This invention relates to belt supporting and aligning structures, and its general objects are, broadly, to provide improvements in structures of this kind.

A more specific object of the invention is to provide an improved belt supporting and aligning structure which is of strong construction, minimum weight and low overall height.

In carrying out the foregoing objects it is another object of the invention to provide an improved belt supporting and aligning structure including a roll supporting frame having an odd number of interconnected spaced legs adapted to carry a plurality of belt supporting rollers and which frame is carried for pivotal .swinging movementthrough the central one of its legs.

Another object of the invention is to provide an im proved idler roller carrying frame, per se, including an odd number of spaced legs adapted to carry a plurality of belt supporting idler rollers and which frame may be carried for pivotal swinging movement through the central one of its legs.

Another object of the invention is to provide an improved belt supporting and aligning structure of strong construction having minimum weight and. low overall height which includes a swingable frame having an odd number of interconnected legs adapted to support a plurality of rollers and in which said frame extends generally in a plane parallel to a belt carried by said rollers and is carried for pivotal swinging movement about an upright axis through the central one of its legs, and in which structure there is, preferably but not necessarily, means carried by said frame adapted to cooperate with means on or carried by the frame supporting means for limiting swinging movement of said frame.

Other objects of the invention will appear hereinafter,

the novel features and combinations being set forth in the appended claims.

In the accompanying drawings:

Fig. 1 is a view in elevation of a conveyer belt sup porting and aligning or training structure with one idler roller removed;

Fig. 2 is a view in section with part broken away, the section being taken on line 22 of Fig. 1;

Fig. 3 is a view on a larger scale taken from the plane 3-3 of Fig. 2 and showing the central portion of the structure seen in Figs. 1 and 2 in section and elevation;

Fig. 4 is a View in section, the section being taken sub stantially on line 44 of Fig. 2;

Fig. 5 is a view in plan of the swingable idler roller supporting frame of the apparatus;

Fig. 6 is a view in plan, on a larger scale, of the central leg of the frame seen in Fig. 5;

' Fig. 7 is a view in perspective of one of the nuts employed to mount the ends of the conveyer rollers in the legs of the frame seen in Fig. 5; and

1 Figs. 8 and 9 are views in perspective of one of the straps that hold the nuts at the ends of the idler rollers in the arms of the frame seen in Fig.- 5.

In the endless belt conveyer art it has long been the practice, particularly in relatively long conveyers, to place between the usual spaced, fixed or stationary belt supporting idler roll stands thereof one or more idler roll structures for supporting theendless belt and for automatically aligning or training it as it travels between the head and foot pulleys of the conveyer apparatus. Numerous types of such devices operating upon different princi ples have been proposed and they have been employed with various degrees of success. Probably the most successful of the apparatuses is that class of them to which the present invention belongs and which includes two or more idler rollers mounted to support the belt and to be swung about a central upright axis in response to uneven or unsymmetrical downward pressures or loading upon the idler rollers with respect to the upright axis about which they swing to cause the idler rollers to swing pivotally from a plane lying at right angles to the direction of travel of the belt to a plane in which they cause the belt traveling over them to shift laterally thereby to compensate for said uneven loading or off-center operation of the belt and, consequently, to maintain the belt in proper alignment as it travels between the head and foot pulleys of the conveyer apparatus.

Of the known structures of the type to which this invention relates, probably all have operated successfully to support and train the conveyer belt but they require the conveyer apparatus in which they are empolyed to be of greater overall height and weight than is desired and this because the known belt aligning or training structures are themselves of relatively great height. One factor which contributes to this large overall height of the known belt supporting and aligning or training structures is the fact that they must include structural supporting frames for the idler rollers which are of great strength in order to support the idler rollers rigidly and this is particularly true where the idler rollers are readily removable from their supporting frames since in such cases the shafts of the idler rollers are merely supported at their opposite ends and contribute little to the rigidity of the assembly, that is, they are carried or cradled through their opposite ends in their swingable supporting frame and the supporting frame, therefore, must be very rigid in order to support the idler rollers properly. One problem met with in this art is that of reducing the overall height of such belt aligning and training roll assemblies while providing in them sufiicient strength to support the idler rollers properly. a

By this invention a very compact, strong and light belt aligning and training idler roll assembly as well as a very light, strong and rigid swingable idler roller supporting frame has been provided which may be of less overall height than any other now known and which, therefore, permits of its use in conveyer apparatus having a minimum overall height.

The conveyer belt supporting and aligning or training structure 2%), seen in the drawings, is of low overall height, that is, it may occupy a space in a conveyer apparatus the vertical dimension of which is very small. It includes a fixed or stationary main frame or base 21 that supports a swingable frame 22 for pivotal swinging movement about an inclined axis and which swingable frame in turn car ries two idler roller assemblies 23 that may rotate inde-- pendently of each other and which function to support and train a run of an endless belt conveyer 24 as it travels thereover.

of upstanding flanged brackets or legs 26 welded to the ends of bar 25 that may be bolted or otherwise fastened to any suitable support means such, for example, as main frame elements not shown, of the conveyer apparatus of which belt 24 forms a part, or any other suitable Patented Feb. 19, 1957 supportingme'ans. Barextends transversely of the lever by a cap 28 and bolts29 that extendthrough aligned? ears or: lugs on the bracket 27' and cap 28. In order to insure that the bracket or leg 27 cannotrotate (in the fixed supporting bar 25,, the bracket or leg 27' includes a. key slot thatrfits upon a rectangular key 30. welded to the bar 25. Bracket or leg 27 may be considered as part of the main frame 21, or per se, asa main support for the swingable frame 22- since all of the weight of the swing: able frame 22 and the elements carried thereby are supported by this bracket or leg.

Bracket or leg 27 is a casting, and at its free end it includesa clamp type socket or fist 31 in which the lower portion of an upstanding pivot shaft 33 is clamped by a bolt and nut-32; Pivot shaft 33 iscarried by the bracket or'leg 27 so that its longitudinal axis lies in a vertical plane extending longitudinally of the belt 24 and in a plane. that extends transversely of the belt 24 and slopes upwardly in the direction of its travel at a preferred angle of with respect to a vertical plane. It may be mentioned that while this upward slope of 30 is preferred, it is not criticalto the operation of the apparatus and it may be varied in a relatively wide range.

The swingable frame 22 is generally E-shaped in plan (see Fig. 5) and it includes an odd number of spaced generally parallel legs including a pair of similar end legs 34 and a central leg 35 interconnected and symmetrically spaced by a main body member in the form of a tube 36 to which they are mounted in cantilever. Endlegs' 35 are castings that include socket portions in which the ends of said body member 36 extend and are fixed' as by welds indicated at 37 in Figs. 1 and 5 of the drawings.

The central leg 35 is a casting carried by the body member 36, spaced centrally between the end legs 35 and clamped to the body member 36 by a cap 38 and screws 39. Screws 39 extend through ears on the cap 38 and into tapped openings in the bracket or leg 35 as clearly shown in Fig. 2 of the drawings. To insure that the main body member 36 and central bracket or leg 35 cannot rotate with respect to each other a key 40, similar to key 30,- is Welded to the body member 36 and is received in a keyseat in the leg 35.

It is important to note that the swingableframe 22 is supported for pivotal swinging movement solely through its supporting leg 35. For this reason the central leg 35 includes a bore 41 at its free end into which the upper end of pivot shaft 3-3 extends. Pivot shaft 33 istmounted through a pair of spaced antifriction bearings 42 fitted against shouldersin the bore 41 and secured upon the end: of shaft 33 bya nut 43 which is protected or covered, in agrease tight manner, by a cap 44 pressed into the upper endof bore 41. The lower end of bore'41 is sealed in a grease and dirt tight manner to the pivot shaft 33 by grease seal means indicated at 44.

The three spaced legs 34 and 35 carry, supportsor cradle the two idler, rollers 23 in axial alignment between them. and for this purpose the central leg. 35 is provided with a pair of oppositely,' laterally extending.

aligned earsorbosses. that are slotted as at 45 to. receive flanges 46 on the endsof nuts 47 which form parts: of. the removable'idlerroller assemblies 23.

In the apparatus. shown in, the drawings the central axis of pivot shaft 33 and the central axes ofrthe idler rollers 23 intersect. While this relation of these;axes is desirable, it; is not critical and the upright pivot axis may be positioned anywhere along the central leg,35-, that is it may be tbetWeenthe main memberq36 and the axes of; the;idler roller 23, or the axes ofthe idler rollers 23' maybe betweensitandthe main-body 36.

Therend legs 34 are also slotted in their free ends at 48' toreceive a nut'47, and in the embodiment of the invention shown, the slots in the central leg 35 and the slots 48 in the end legs 34 are in axial alignment.

The idler rollers 23 shown in the drawings are of a well-known type in which there is a hollow, central dead shaft 49 (see Fig. 3) about the axis of which the shell of the idler roller rotates. Each end of the dead shaft 49 carries one of the nuts 47- which is grooved adjacent its outer end; as at 50, toprovide the end flange 46. When the idler rolls 23 are' cradled; inthe swinging frame 22 the circumferential grooves 50 of these nuts 47 are received by the slots 45' and-48 inthe legs 35" and 34 respectively and they are retained against axial movement within the swinggble. frame 22'thereby. The idler rollers 23 are held in the legs 34 and 35 by U-shaped straps 52 each of which covers one'ofthenuts 47 and has a deformed portion 53 which extends into the circgmferential groove 50. The U-shaped straps are fastened to the legs 34 and 35 of theswingable frame 22 by cotter keys 54 that extend through the .legs'of the straps 52 and the legs 34 and 35.

The central leg 35 of swingable frame 22 also includes a pocket 55. adjacent each of the slots 45. These pockets 55 each receivev one of'the end flanges 46 of a nut 47 and a compressible wedge shaped cylindrical seal elementSfi formed of any of the well-known grease resistant synthetic rubbers. These sealing elements 56 are. retained in the. pockets 55. by the U-shaped straps 52 which cover them and they each exertpressure upon the end of the nut 47 and. the. opposite side. of the pocket 55, thereby. resiliently aiding in preventing endwise. or axial movement of the idler rollers 33 with respect to the swingable frame -22.

As indicated in Figs- 2 and 3 of the drawings, the cen: tral leg 35 includes aligned bores 57 that connect the hollow dead shafts,49 of'the idler rollers through central openingsoin the compressible seal elements 56 with the bore 41 which encloses the pivot bearings 42. Because the bearings. nottshown, for supporting the idler rollers 23 on the dead shafts 49 receive lubricant, such as grease, from the central bores 58 of the dead shafts 49, all of the hearings in both. idler rollers 23 and the bearings 42 may be lubricated merely by forcing lubricant through a grease fitting 59 in the end of one of the shafts 49 at a leg 34.

It has been found in practice that it is desirable that the: range in swing of the frame 22 about the axis of pivot shaft 33. should be limited, and to this end the support bracket or leg 27 is provided with a pair of upstanding spaced ears orlugs 60 (see Figs. 2 and 4) that cooperate with an ear or lug 61 on the central leg 35 of frame 22, which extends between the ears or lugs 61 and. is adapted:to abut one of them when the frame has been swung in either direction a predetermined amount.

From the. foregoing it will be seen that the swingable frame 22 is carriedsubstantially at the center of its length and, therefore, substantially at the longitudinal center of gravity of itself, the rollers 23 and other items carried by it. It willalso be seen that frame 22 is supported solely through its central leg 35 for pivotal swinging movement about the'upright axis of pivot shaft 33 and that the swinging. movement is restricted within, desired limits by the cooperating ears or lugs 60 and 61 associated with the swinging and stationary frames 22 and 21 respectively. The main body member 36 and legs 34 and 35 of frame 22 all lie or extend in a generally horizontal plane below the upper rim of belt 24 and its main member 36 lies at one side of the idler rollers -23 and substantially directly above the supportbar, 25 ,of main frame21. It will be noted that the pivotal connecting; apparatus including the bearings 42am contained .within the cylindrical, confines'of and betweenthe idler, rollers 23 and "that the entire frame;

22 lies within the vertical confines of the idler rollers 23.

thereby removing the swingable frame as a height adding factor in the apparatus 20. All of these features cooperate to provide a very compact belt supporting and aligning structure which, of course, permits of the construction of conveyer apparatuses including such structures to have a minimum overall height and, therefore, a minimum of weight accompanied by maximum strength.

While the idler roll apparatus 20 shown in the drawings includes only two of the idler rollers 23 it is to be understood that any number of idler rollers may be used so long as they are arranged symmetrically with respect to the center leg 35 of the swingable frame 22. It is also to be understood that the idler rollers need not lie upon a common axis. For example, they may be arranged to carry a troughed belt.

Obviously those skilled in the art may make various changes in the details and arrangement of parts without departing from the spirit and scope of the invention as defined by the claims hereto appended, and applicant therefore wishes not to be restricted to the precise construction herein disclosed.

Having thus described and shown an embodiment of the invention, what it is desired to secure by Letters Patent of the United States is:

1. A conveyer belt supporting and training idler roll assembly of low overall height including a stationary frame having an elongated tubular support means adapted to extend transversely of said conveyor belt, a fixed leg mounted in cantilever on said tubular support means extending laterally and generally horizontally therefrom, means forming a fist at the free end of said fixed leg, an inclined upstanding pivot shaft in said fist, a roller supporting frame above said stationary frame including an elongated tubular member positioned substantially directly above said elongated tubular support means, a plurality of spaced legs including a central leg mounted in cantilever on said tubular member extending laterally and generally horizontally therefrom, roller means carried between said last named legs, said central leg lying substantially directly above said fixed leg, a bore in said central leg adjacent the free end thereof, antifriction bearing means in said bore and mounted on said pivot shaft whereby said roller supporting frame may swing about said pivot shaft, and means on said central leg and said fixed leg cooperating to limit swinging movement of said roller supporting frame with respect to said stationary frame.

2. A conveyor belt supporting and training idler roll assembly of low overall height including a stationary frame having an elongated support means adapted to extend transversely of said conveyor belt, a fixed leg mounted in cantilever on said support means extending laterally and generally horizontally therefrom, a roller supporting frame above said stationary frame including an elongated member positioned substantially directly above said elongated support means, a plurality of spaced legs including a central leg mounted in cantilever on said elongated member extending laterally and generally horizontally therefrom, roller means carried between said last named legs, said'central leg lying substantially directly above said fixed leg, pivot means interconnecting said fixed leg and said central leg whereby said roller supporting frame may swing with respect to said stationary frame, and means on said central leg and said fixed leg'cooperating to limit said swinging movement of said roller supporting frame.

3. A conveyer belt supporting and training idler roll assembly of low overall height including a stationary frame having an elongated support means adapted to extend transversely of said conveyer belt, a fixed leg mounted in cantilever on said support means extending laterally and generally horizontally therefrom, a roller supporting frame above said stationary frame including an elongated member positioned substantially directly above said elongated support means, a plurality of spaced legs including a central leg mounted in cantilever on said elongated member extending laterally and generally horizontally therefrom, roller means carried between said last named legs, said central leg lying substantially directly above said fixed leg, and pivot means interconnecting said fixed leg and said central leg whereby said roller supporting frame may swing with respect to said stationary frame.

4. Idler roller supporting structure including a roller supporting frame having an elongated main member, a plurality of spaced legs including a central leg mounted in cantilever on said elongated member extending laterally and generally horizontally therefrom, roller means carried by said spaced legs between said legs, said spaced legs and main member lying substantially wholly within the vertical confines of said roller means and with said main member at one side thereof, and means adjacent the free end of said central leg by which said frame may be mounted for swinging motion about an inclined axis.

References Cited in the file of this patent UNITED STATES PATENTS 1,963,099 Robins June 19, 1934 2,225,276 Parker Dec. 17, 1940 2,305,036 Salfisberg Dec. 15, 1942 2,399,913 Dodge May 7, 1946 

